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211.
This study was conducted to investigate the effects of parity and litter size on gestation length in beagle bitches. The mean duration of the initial elevation (>2 ng/mL) in progesterone concentrations after the onset of proestrus was shorter (P < 0.05) in bitches without (nulliparous) whelping experience than in bitches with (multiparous) whelping experience (6.9 d versus 8.0 d). When calculated as the interval between the day of initial elevation in progesterone concentrations and the day of whelping, the gestation length in the nulliparous bitches was noted to be similar to that in the multiparous bitches (64.3 d versus 64.2 d). No significant correlation between gestation length and litter size was observed in any of the bitches. Our results indicate that the gestation length in beagle bitches is not affected by parity or litter size.  相似文献   
212.
迎风向防风林带宽对风速减弱的作用   总被引:2,自引:1,他引:1  
通过在日本扎晃人学水压力工程实验室开展的埃菲尔型非循环风洞试验,研究了防风林阻尼变化及不同林带宽的整体阻力系数,阐明在迎风向上防风林带宽对风速减弱的作用.以二维雷诺时均N-S方程-k-ε吨扰动闭合模型数字地研究了不同防风林带宽的流量场变化.结果表明,防风林对风的阻力随林带宽增加而增加,但是整体阻尼系数略微降低.整体阻尼系数Cd、防风林带宽W和林高H之间满足方程Cd=kd(W/H)-b(kd,b:常数).数字模拟结果表明,防风林带宽度明显影响最小风速值及其位置.随着防风林带宽度的增加,风速下降15%-22%.  相似文献   
213.
Ocean Expo Park, established in 1976 on subtropical Okinawa Island, Japan, has approximately 8000 planted or naturally grown trees in an area of 77.2 ha. Windfall of these trees occurs mainly due to typhoons; wood chips made from the trunks and roots of windfall trees are commonly used as mulching material throughout the park areas, despite possible infection by pathogenic fungi such as Phellinus noxius, the pathogen causing brown root rot. P. noxius is distributed in tropical and subtropical areas worldwide and has a broad host range. The fungus can infect host plants with mycelia via root-to-root contact or with basidiospores. Here, we report the current status of tree damage caused by brown root rot in the park and infer the infection routes of P. noxius based on microsatellite markers. Among a total of 294 trees surveyed in the park, P. noxius was isolated from 13 trees of five species. P. noxius was observed more frequently on Ficus microcarpa than on other tree species. Ficus superba var. japonica was identified as a new host species, and Bombax ceiba was first recorded as a host plant of P. noxius in Japan. Among the 13 P. noxius isolates from the diseased trees, 2 isolates from adjacent diseased trees were considered to be of the same genet, while the other 11 isolates were different genets, indicating that infection by basidiospores occurred frequently among trees in the entire park, although spread via root systems also occurred between at least two adjacent trees. An identical genet was not detected at distant locations, which suggests that the disease does not spread via chips. However, mulching with chips can lead to wood decay due to decaying fungi other than P. noxius. Therefore, in accordance with the precautionary principle, the park currently prohibits the chipping and mulching of windfall or damaged trees and is considering disposal methods such as burning.  相似文献   
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A new prenylated flavone, named artoindonesianin L (1), was isolated from Artocarpus rotunda (Hout) Panzer (Moraceae). Its structure was elucidated as on the basis of spectroscopic evidence. Along with this new compound, four known phenolic compounds were also isolated from this plant and identified as artonins M (2) and E (3), cycloartobiloxanthone (4) and artonin O (5). All these compounds showed significant cytotoxicity against murine P388 leukemia cells.  相似文献   
217.
There is an urgent need for the international community to address not only the issues of preserving the global environment and reducing poverty in developing countries, but to also face up to new challenges, such as providing assistance to the reconstruction in Afghanistan. Furthermore, it is necessary to address these issues and challenges by means of mutual collaboration. This latter point has been the subject of lively discussion.In this paper, we describe a new direction in international cooperation taken by the Rural Development Bureau of the Ministry of Agriculture, Forestry and Fisheries, Japan in response to the trend of international discussions. This shoulb be achieved by utilizing Japans experience and expertise gained in the development of its own paddy rice agriculture.Specifically, based on the philosophy that sustainable agricultural and rural development can conserve a regional environment, the Bureau intends to undertake: (1) extension of the results from a cooperation project to other regions, by modifying it and converting it to multi-purpose use; (2) collaboration with aid-related entities in Japan and abroad, and dissemination of related information to them; and (3) promotion of cooperation focused on a specific topic.Furthermore, the Bureau will promote the following matters as the basis for international cooperation in each major task. (1) Contribution towards sustainable water use. (2) Extension of the participatory integrated rural development, and its modification for reconstruction assistance. (3) Extension of desertification control, and its modification and conversion for multi-purpose use. (4) Conversion of the technology for soil erosion control into multi-purpose use.  相似文献   
218.
This study was conducted to determine the effect of pelleting on in situ dry matter degradability of pelleted compound feed containing brown rice for dairy cows. Mash feed of the same composition was used as a control and the in situ study was conducted using three non‐lactating Holstein steers fitted with a rumen cannula. The feeds contained 32.3% brown rice, 19.4% rapeseed meal, 11.4% wheat bran and 10.6% soybean meal (fresh weight basis). Except for moisture content, the chemical composition of the feed was not affected by pelleting. In situ dry matter disappearance of the feed increased from 0 to 2 h and after 72 h of incubation with pellet processing. Integration of the dry matter disappearance values over time revealed that degradability parameter a (soluble fraction) increased with pellet processing, whereas parameter b (potentially degradable fraction) decreased. Parameter c (fractional rate of degradation) and effective degradability (5% passage rate) were not affected by pellet processing. We concluded that pellet processing promotes rumen degradability at early incubation hours when the pelleted feed contains brown rice.  相似文献   
219.
The enhancing effect of cross-linked ricin (CL-ricin) on the cell-mediated and humoral immune response of mice to non-viable Mycoplasma pulmonis was studied. The cell-mediated immune response was evaluated by means of the delayed-type footpad swelling, and the humoral immune response by means of the indirect hemagglutination test. Mice pre-treated subcutaneously with non-viable M. pulmonis and CL-ricin showed significantly increased delayed-type footpad swelling when they were injected in the footpad with the same antigen 7 days later. Delayed-type footpad swelling was not detected in mice pre-treated only with non-viable M. pulmonis or CL-ricin followed by footpad injection with non-viable M. pulmonis. Injection of non-viable M. pulmonis in the footpad on Days 3, 7, 14, 21, 28, 35 and 42 after pre-treatment with non-viable M. pulmonis and CL-ricin resulted in significant footpad swelling. Delayed-type footpad swelling was transferred by intravenous injection of spleen cells from mice which had been pre-treated 7 days previously with non-viable M. pulmonis and CL-ricin into non-treated recipient mice. Intravenous injection of anti-mouse thymus cell serum into mice previously pre-treated with non-viable M. pulmonis and CL-ricin reduced the delayed-type footpad swelling significantly. Mice pre-treated subcutaneously with non-viable M. pulmonis and CL-ricin showed a marked increase in serum antibody titers compared with those that received non-viable M. pulmonis alone.  相似文献   
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